Astronaut twin experiment results surprising

Astronaut Scott Kelly spent 340 days aboard the space station while his twin brother remained on Earth.

This extended stint in space gave scientists at NASA a unique opportunity to study what impact space travel has on the human body by comparing the health of both twins before Scott Kelly traveled to the International Space Station and then again after he had came back.

It was expected that spending time in space would have a detrimental effect on his health, but to everyone's surprise it turned out that one key ageing process actually seemed to have reversed.

Telemores, which are responsible for repairing damaged DNA, get shorter as we age which also reduces their effectiveness and makes us more prone to diseases such as cancer.

Remarkably however, Scott Kelly's telemores seemed to have actually increased in size relative to those of his brother while he was in space - the total opposite to what would be expected.